The honey bee gut microbiota: a review under the perspective of bees threatened by agrochemicals

Abstract

Although it is very well known that bees play a key role in the stability of several ecosystems globally, anthropogenic activities causing environmental degradation, such as the use of agrochemicals, can ultimately lead to the extinction of native species, with severe ecological consequences. The advances in high throughput sequencing technologies and bioinformatics tools in the last decades have contributed to the understanding of the importance of the microbiome for the health of different animal species. However, there is a paucity of information on the effects of the exposition to agrochemicals on the microbial composition of honeybees and how this can compromise their health. In this systematic review article, we discuss the composition and biological function of native honeybee gut microbiota and how it can be possibly affected by agrochemicals, including antibiotics. We performed a systematic literature review focusing on the effect of agrochemical use on the gut microbiota of honey bees. A bibliographical survey was conducted from 1950 to 2023 in all available databases. We used the keywords “honey bees”, “microbiome” and “agrochemicals”. A total of 95 papers addressing this topic were selected, carefully checked and grouped into three categories: 1) The bee microbiome and its importance; 2) Functional roles of the bee gut microbiome; and 3) The problem of the anthropic actions that threaten the gut microbiome of bees. The present report can serve future studies addressing the complex ecological aspects of antimicrobial usage in agriculture and livestock in the scope of honeybee preservation.